Abstract

Ferroelectric liquid crystal electrooptic shutters/choppers offer the advantages of low drive voltage and ease of use. Previous devices use the liquid crystal as a switchable halfwave plate between crossed polarizers. Since they are first-order wave plates, they have a reasonably wide spectral range, but their extinction is limited by the ability to control the wave plate to sufficient precision. The use of linear polarizers severely limits the efficiency. We show here how shutters/choppers for collimated light beams can be made using total internal reflection from liquid crystal films instead. This approach produces devices with much better extinction and efficiency.

© 1988 Optical Society of America